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Anyone know anything about props

  • 10-06-2013 09:19PM
    #1
    Registered Users, Registered Users 2 Posts: 166 ✭✭


    Well lads just wondering does anything know anything about changing the prop on a 9.9 mariner to get more speed out of it.

    I know people are going to say buy a bigger engine, but I just can't afford it this year.

    Boat is a 16+ Orkney strikeliner and engine is an 04 9.9 mariner. Boat will do about 8 knots with 3 people on board and I'm just looking to see Is there a way to get a little bit more speed out of it while saving for an upgrade. She is very light on petrol as is. About 10 liters for whole days fishing, so I wouldn't mind sacrificing this for a bit more speed.


Comments

  • Registered Users, Registered Users 2 Posts: 166 ✭✭marcp


    Just realized this is in the wrong section. Could an admin move it to the boating section please.


  • Moderators, Motoring & Transport Moderators, Sports Moderators, Paid Member Posts: 6,385 Mod ✭✭✭✭fergal.b


    Changing your prop to a higher pitch will give you a better top end speed but a slower takeoff speed "hole shot" I think the pitch for your engine can be anything between 7 & 10.




    .


  • Registered Users, Registered Users 2 Posts: 691 ✭✭✭stylie


    I have two props for my 15hp, stock prop and one with the higher pitch to over rev her. You get a slight increase in top speed but I feel your burning a lot of petrol for a small increase in speed.
    You might be able to adjust/change the carb, this is popular on the old Johnson 9.9s as they are almost identical to the 15's anyway and it certainly makes them a lot faster than your average 9.9.
    You might be able to do this with your engine, seems to work on older models of 9.9s


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